Puzzle, puzzle piece and method for making puzzle

ABSTRACT

The present invention aims to provide a jigsaw puzzle in which pieces are kept at a certain size or smaller and can interlock with other pieces, even if rotated, and to enhance a game-playing property and an interlocking property at the time of assembling such a jigsaw puzzle. A jigsaw puzzle piece  1  can interlock with other pieces  1  by interlocking portions each composed of at least one pair of projections  10  and recesses  11  and provided on a corresponding one of four sides of a rectangle. The respective sides are shaped to be point symmetrical with respect to a center  12  of the rectangle, and the piece can interlock with other pieces regardless of its orientation. Curvatures of a cutting die are maximized by slight inclinations of the respective pieces. By assigning a short-distance visible mark  20  to  22 , which makes the orientation of the piece discriminable, to the top surface of each piece, a game-playing method can be provided which is different from assembling of conventional jigsaw puzzles.

TECHNICAL FIELD

The present invention relates to jigsaw puzzle pieces and a tray used toarray jigsaw puzzle pieces, particularly to a technology characterizedby the shape and display of the pieces.

BACKGROUND ART

As widely known, jigsaw puzzles are games in which one complete image iscut and separated into the configuration of a puzzle, and the respectivepuzzle pieces are fitted together using the projections and recesses ofthe outer edges and parts of the image drawn on the pieces as a clue.Many jigsaw puzzles are produced by printing a complete image on acardboard surface and cutting the cardboard into various patterns.

Generally, as shown in FIG. 10, the cardboard is die cut in twoprocesses: (a) first, by die cutting in a horizontal direction and (b)second, by die cutting in a vertical direction, thereby (c) producingpieces in a cut pattern which are blocked-in in vertical and horizontaldirections.

The shapes of the respective pieces in jigsaw puzzles cut like this aresubtly different while being similar, and a player enjoys finding theslight differences. Most jigsaw puzzles are produced in this manner,since many elements of reasoning are involved and the positions of thepieces are less likely to be found based on their shapes, even if thegame is repeatedly played.

There is also a method to die cut random patterns in one procedure, asshown in FIG. 11. Jigsaw puzzles with such patterns have various pieceshapes, creating the difficulty and unpredictability that the shapes ofneighboring pieces cannot be inferred. The applicant of the presentapplication has also taken advantage of the feature that free shapes canbe generated to produce a jigsaw puzzle with silhouette pieces; formingthe respective pieces into special shapes such as those of cats and dogsto increase fun during assembly.

In conventional jigsaw puzzles, piece designers exercise their ingenuityto form lines of pieces so that, for example, no two pieces out of even1000 pieces have the same shape. The game-playing property of a jigsawpuzzle largely depends on the quality of the cut pattern.

The fun of a jigsaw puzzle lies in arraying the pieces, while using thepiece shapes and images on the surface of the pieces to guess theirpositions on the complete image.

On the other hand, there is also a product that is laid on the floorcalled a puzzle mat. This is a thick mat made of EVA (ethylene vinylacetate), which is used by placing together, for example, substantiallysquare pieces measuring about 30 cm on each side. A multitude ofprojections and recesses on peripheral edges of the respective piecesinterlock with projections and recesses of other pieces, therebyavoiding friction.

In the puzzle mat, a picture is drawn on each piece and thereforeassembling the pieces does not form one complete image. Thus thesymmetrical asperities of the pieces often make them capable ofinterlocking in arbitrary directions. Because the puzzle mat pieces caninterlock in arbitrary directions for practical utility, orientationsneed not be considered to arrive at a complete image like jigsawpuzzles.

Patent document 1, making a proposal based on a similar idea, disclosesa jigsaw puzzle that can be connected in both vertical and horizontaldirections. According to the disclosure, projections and recesses arerespectively provided near corners of each side of the piece body.Projections and recesses of two piece bodies can interlock with eachother, in a state where the arbitrary side of one piece body can faceany side of another piece body.

An object of the present invention is to create, not an original jigsawpuzzle in which pieces are arrayed toward a predetermined completeimage, but one that a child can play by freely fitting and changingdirections of pieces with parts of streets drawn on them. Thus, imageson the respective pieces have to tell directions in which the piecesshould be arranged.

Patent document 2 discloses a technology for forming piece numbers,corresponding to arrangements and interlocking directions of pieces, onthe undersides of vertical pieces and horizontal pieces. This is atechnology for assigning numbers, e.g. in the form of A-1, B-2 to reducetime and effort to specify the pieces. A player can complete a jigsawpuzzle without considering shapes and patterns by arraying the piecesaccording to the numbers, but this technology does not contribute toenhancement in the game-playing property of the puzzle.

CITATION LIST Patent Literature Patent Document 1:

-   Japanese Unexamined Patent Publication No. 2001-113036

Patent Document 2:

-   Japanese Unexamined Patent Publication No. 1997-299610

SUMMARY OF INVENTION Technical Problem

As described above, the game-playing property of the jigsaw puzzle liesin that the positions of the respective pieces on the predeterminedcomplete image can be guessed based on the shapes and patterns of thepieces. Since the shapes are respectively changed, how the respectivepieces are fitted together cannot be changed. On the other hand, in thecase of a puzzle in which pieces can be fitted together, even if theorientations thereof are changed, as disclosed in patent document 1, nopredetermined complete image exists and the pieces can only be freelyfitted together, wherefore there is no game-playing property of thejigsaw puzzle.

Furthermore, conventional puzzles where pieces are fitted together withthe orientations thereof freely set, have one projection or one recesson each piece side, as shown in FIG. 13, and can be rotated only in twodirections, regardless of whether the piece is one with each side of 30cm or longer as shown in FIG. 12 or a small one with each side of 3 cmor shorter. In a cutting die for a jigsaw puzzle fabricated by a bendingsteel, there is a physical limit to the number of projections andrecesses which can be set within a given distance. It is alsotechnically difficult and not particularly necessary to form pieces thathave the same shape and can be precisely fitted together, even iforientations are changed.

However, in the case of a jigsaw puzzle in which individual pieces areonly printed with single-color gradation patterns and one image appearswhen all the pieces are assembled, such as a jigsaw puzzle relating tothis application, a complete image must be viewed at a specifieddistance and each piece side is required to be about 1 to 2 cm in orderto enjoy the complete image in a room by hanging the puzzle on a wall.

In order to enable the projections and the recesses to interlock witheach other, even if the arrangement of the pieces is changed, all thepieces must have a congruent shape. In order to allow the respectivepieces to rotate in four directions, each side needs to be provided withone or more pairs of projections and recesses, as shown in FIG. 14( a).In such a case, image information in the central part is impaired ifinterlocking portions have a relatively large size, as shown in FIG. 14(a).

As a result, what is required is a shape in which interlocking portionsare arranged only at peripheral parts, as shown in FIG. 14( b). Asdescribed above, in the jigsaw puzzle of this application, a fairly highlevel of working accuracy is required to satisfy all the requirements:that the piece size is 1 to 2 cm, one or more pairs of projections andrecesses are arranged on each side, all the pieces have a congruentshape and are point symmetrical with respect to the centers thereof, andas large a central part as possible is left.

For example, a pinnacle die is a corrosive blade sharpened by meltingsteel and is capable of die cutting with high accuracy, but is used fordie cutting stickers and can only die cut materials that have athickness up to about 1 mm. Normally, the thickness of a jigsaw puzzleis about 1.8 mm. With a thickness of 1 mm, the pieces poorly interlockwith each other and a comfortable game-playing property cannot beensured.

Plastic pieces can be worked by die molding, but have higher cost, asmaller degree of freedom in printing as compared with paper jigsawpuzzles, and lack an advantage also in the paper feel sought by jigsawpuzzle lovers.

In the case of fabricating a cutting die for die cutting cardboard, asin the present application, a steel sheet having an entire length of 20m is successively bent, wherefore a degree of difficulty in precisebending increases as the piece size decreases.

The present invention was developed in view of the above conventionaltechnology, and the object thereof is to provide a jigsaw puzzle whichhas a piece size of 1 to 2 cm, with pieces that can interlock with otherpieces, even if exchanged or rotated, is produced by die cuttingcardboard, and that enhances a game-playing property and an interlockingproperty at the time of assembling pieces in such a jigsaw puzzle.

Solution to Problem

In order to solve the above problems, the present invention proposes ajigsaw puzzle piece as described below.

Specifically, this jigsaw puzzle piece can interlock with other piecesby interlocking portions, each composed of at least one pair ofprojections and recesses, provided on a corresponding one of four sidesof a square. The respective sides are formed to be point symmetricalwith respect to a center of the square and the piece can interlock withother pieces in four upward, downward, leftward and rightwarddirections. The respective sides of the piece are shaped such thatprojection-adjacent-side-portions, adjacent to the projections, aredisplaced inwardly of the square and recess-adjacent-side-portions,adjacent to the recesses, are displaced outwardly of the square withrespect to a virtual reference line composed of sides of a square.

Further, the projections and the recesses are moved on the virtualreference line by distances corresponding to respective displacements,thereby preventing uneven portions to sides of adjacent pieces whenpieces interlock with each other, and the maximum width of enlargedportions of the projections is set larger than the minimum width ofconstricted portions of the recesses to prevent detachment ofinterlocked projections and recesses.

According to this construction, curvatures of connecting portions of theprojections and the recesses of the sides can be increased by displacingthe adjacent side portions. Thus, constriction of the interlockingportion necessary for interlocking can be easily produced, whichparticularly contributes to an improvement in interlocking property atthe time of assembling small pieces with each side of 2 cm or smaller.

Further, a game-playing property at the time of assembling the pieces isenhanced by assigning a short-distance visible (long-distance invisible)mark to the top surface of the piece, capable of specifying the pieceand its orientation in addition to complete image information of thepuzzle.

The above short-distance visible mark is displayed due to a differencebetween two or more reflectances, glazes, or surface roughnesses and canbe easily made, for example, by printing using varnish or the like.

The present invention can also provide a tray used to array theplurality of pieces described above.

In this tray, an outer edge coincides with the size of a jigsaw puzzlein a completed state, a frame body is prepared along four sides toprevent detachment of the pieces, and row and column indicators areprovided to indicate vertical and horizontal positions of the respectivepieces.

ADVANTAGEOUS EFFECTS OF THE INVENTION

The present invention has the following effects by including the aboveconstruction.

Specifically, it is possible to provide a jigsaw puzzle whose pieces caninterlock with other pieces, regardless of their orientations, by havingthe respective sides thereof shaped to be point symmetrical. Since theorientation of the piece capable of interlocking in the respectivedirections is specified by the short-distance visible mark, a processcorresponding to the conventional operation of setting the orientationof the pieces based on their outer shape can be created, whereby thegame-playing property as a jigsaw puzzle can be enhanced.

Simultaneously, even with a minimum projection and recess curve forforming reverse tapers, which has been difficult to form forconventional small pieces, interlocking is possible by displacing theside portions adjacent to the projections and the recesses to increasecurvatures of the projections and the recesses. By doing so, the piecesdo not come off when being assembled, and the game can be comfortablyenjoyed.

Further, since the curvatures can be increased, working accuracy of theprojections and the recesses can be ensured and a piece that accuratelyinterlocks, even if its position and orientation is changed, can beprovided.

By the short-distance visible mark, pieces that are difficult todistinguish based on the image on the piece can be specified and theorientation can be determined, even if the piece shape makes it capableof interlocking in each direction. Thus, such as at the time of enjoyinga conventional jigsaw puzzle, an operation corresponding to the processof assembling the entire puzzle based on images printed on the piecesurfaces can be created and the game-playing property as a jigsaw puzzleis enhanced.

In the construction of the short-distance visible mark, due to thecontrast between two or more reflectances, glazes, or surfaceroughnesses, the differences hardly stand out when the mark is seen at adistance and do not affect the expression of the complete image of thepuzzle. On the other hand, when the picked-up piece is seen at the timeof assembling, the piece and its orientation can be specified becausethe difference in light reflection is clearly visible, wherefore thepuzzle can be assembled.

According to the tray of the present invention, the pieces can be lookedat and directly arranged at correct positions as with a conventionaljigsaw puzzle since positions where the respective pieces should bearranged can be confirmed on the tray. In some conventional puzzles forsmall children, indicators showing the outer shapes of pieces are madeon a tray and the pieces are assembled by comparing the outer shapes.However, since the pieces of the present invention have a congruentouter shape, such an arrangement is impossible. In this respect, thepieces can be arranged on the tray of the present invention based on therow and column indicators. Therefore, the pieces can be successivelyarrayed from those whose positions are found out in the same manner asbefore, which contributes to an improvement in the game-playingproperty.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1( a) and (b) are diagrams showing the pattern and short-distancevisible mark on the surface of a jigsaw puzzle piece according to thepresent invention,

FIG. 2 is a diagram showing an exemplary piece array table byshort-distance visible marks according to the present invention,

FIGS. 3( a) and (b) are views of exemplary piece images and oneembodiment of an assembled image,

FIGS. 4( a) and (b) are diagrams showing the challenges the presentinvention is facing,

Figure is a diagram that shows a method for die cutting pieces of thepresent invention,

FIG. 6 is a diagram showing the outer shape of the piece according tothe present invention,

FIG. 7 is a diagram showing a state where the pieces according to thepresent invention are arrayed,

FIGS. 8( a) and (b) are views showing an embodiment of theshort-distance visible mark,

FIG. 9 is a plan view showing a tray according to the present invention,

FIGS. 10( a), (b) and (c) are diagrams showing a cutting pattern forconventional pieces,

FIG. 11 is a diagram showing a cutting pattern for conventional pieces,

FIG. 12 is a diagram showing an example of a conventional puzzle,

FIG. 13 is a diagram showing another example of a conventional puzzle,and

FIGS. 14( a) and (b) are diagrams showing the sizes of projections andrecesses of puzzles.

DESCRIPTION OF EMBODIMENTS

Hereinafter, one embodiment of the present invention is describedthrough an example shown in the drawings. Note that examples ofexecution are not limited to the following.

A piece (1) of a jigsaw puzzle according to the present invention isshown in FIGS. 1( a) and (b). FIG. 1( a) shows the surface shape ofapiece and a gradation pattern is printed, as shown. FIG. 1( b) is adiagram showing a short-distance visible mark printed on the surface.The short-distance visible mark is described later.

A first feature of the present invention is the outer shape of thisjigsaw puzzle piece. Namely, one projection (10) and one recess (11)following this projection is formed on each side of a square. Theprojection (10) is formed to be able to interlock with the recess (11)and the respective sides are shaped to be point symmetrical with respectto a center point (12) of the piece (1), whereby the pieces of thepresent invention can be connected with one another in vertical andhorizontal directions. The piece can interlock in any of the fourdirections.

FIGS. 3( a) and (b) show an example of a gradation pattern on a surfacein this embodiment and a complete image formed by arraying such piecesin accordance with an array table of FIG. 2.

FIG. 3( a) shows a sheet printed with various gradations on a surface.The respective pieces are die cut on a cardboard and, for example, about500 pieces are prepared. Only using the necessary pieces out of thesecan form various pictures. Since it is difficult to form a picture basedon a complete image, the pieces are arrayed and fitted together whilereferring to the short-distance visible marks and FIG. 2, based on thearray table prepared beforehand.

FIG. 3( b) shows a portrait of Beethoven using 300 pieces. Usage ofdifferent pieces depending on the picture enables assembly of variousimages. However, since a completed image is a type of mosaic pattern,the picture cannot be recognized unless viewed at a certain distance. Asthe size of the complete image increases, it must be viewed at a furtherdistance. Thus, in order to be appreciated in a general home, it isdesirable that the pieces are a certain size or smaller, e.g. 2 cm orsmaller in order. Accordingly, the outer shape of the piece according tothe present invention will be described.

Firstly, problems inherent in the conventional technology are describedwith reference to FIG. 4. If pieces, (100) with measurements of about 1to 2 cm on each side, should be die cut in vertical and horizontaldirections in two steps as shown in FIGS. 10( a) and (b), there is apossibility that cut positions are relatively displaced, wherefore it isvery difficult to form the respective pieces with a point-symmetricalsquare shape. Also, in the case of die cutting in one step as shown inFIG. 10( c), it is very difficult to bend a steel cutting blade so thatthe individual pieces come to have a completely identical shape.Although it is assumed in this application that the respective piecesare separately die cut as shown in FIG. 5, the respective pieces areshown in a connected state in the following description.

In the case of engaging the projection (111) and the recess (112) asshown in FIG. 4( a), there is a problem that the cutting blade cannot besufficiently bent inwardly at a curved portion (114) due to aninsufficient height (113) (see partial enlarged view (110)) of theprojection. Similarly, the cutting blade cannot be folded inwardly atthe recess (112) due to an insufficient depth.

Since such projections (111) and recesses (112) have no constrictedparts (115), even engaged pieces detach when pulled obliquely, i.e. thepieces are not interlocked. While assembling a jigsaw puzzle, piecesthat are not interlocked may be easily separated when subject tovibration, thereby considerably impairing a comfortable game-playingproperty. Accordingly, a general jigsaw puzzle normally includesenlarged portions with larger widths at the top sides of projections andbottom sides of recesses, constricted portions with smaller widths atintermediate positions of the projections and the recesses, andinterlocking portions, each composed of a combination of the enlargedportions and the constricted portions.

As described above, it was sufficient to design conventional cutpatterns with a curvature, at which the cutting blade can be bentwithout making the respective sides symmetrical. Thus, problems facingthe present invention were not found. For example, each side mightinclude one recess or projection, as shown in FIG. 10, or a free patternleaving symmetry out of consideration, as shown in FIG. 11, could beemployed.

However, in order to interlock pieces that can be rotated in fourdirections and are point symmetrical, as in the present invention, eachside must include one or more pairs of projections and recesses,therefore causing the problems faced by the present invention.

In the case of the present invention, pieces need to satisfactorilyinterlock, regardless of with which piece it is fitted together with,and the shapes of the projections and the recesses need to be retainedwith high accuracy since the orientation and position of the piecediffer every time. The conventional method does not assume aninterlocked state with pieces, other than those that are adjacent, atthe time of die cutting, wherefore there is a problem that the piecesmay not interlock well if a combination is changed.

One solution to these problems is to increase the height of theprojections (111) and the depth of the recesses (112). However, in thecase of producing an image by gradation expression as in the presentapplication, enlargement of the projections and the recesses leads to asmaller central rectangular part as shown in FIG. 14( a), which resultsin a problem in the reproducibility of the complete image. From theperspective of reproducibility, it is desirable for all of the pieces tobe square with no projections and recesses. However, in this case, acomfortable game-playing property is impaired, as descried above. Thegist of the present invention is to provide the interlocking portionswhile ensuring a maximum square area in the center.

Accordingly, there is a proposed method for increasing heights from thesides while keeping size changes of the projections (111) and therecesses (112) to a minimum level.

First of all, a side portion (131) (see partial enlarged view (130))adjacent to the projection (121) of the piece (120) as shown in Figure(b) is displaced inwardly (upwardly in FIG. 4( b)) of a square from theposition of the dotted line (135). Then, the height (132) of theprojection (121) can be increased to increase a curvature of a curvedportion (133). The recess (122) is similarly formed.

According to this method, the projection (121) and the recess (122) canbe formed with constricted parts, wherefore interlocking is possible.

However, the side portion (134) adjacent to the recess (122) isdisplaced outwardly of the square while the side portion (131) adjacentto the projection is displaced inwardly, creating unevenness where thetwo sides come into contact.

As is clear from a partial enlarged view (140), there is unevennessbetween side portions (141) and (142), adjacent in a lateral direction,and between side portions (143) and (144), adjacent in a verticaldirection, with the result that a space (145) is formed between fourpieces.

If the pieces are arrayed in this way, they are clearly sloped down tothe right while forming steps. Therefore, when all the pieces arearrayed, they constitute the shape of a parallelogram, which impairs theexternal appearance.

Accordingly, in the present invention, a pair of projections andrecesses is formed on each side of a piece (200) based on a squarevirtual reference line (240). Projection-adjacent-side-portions that areadjacent to the projections are displaced inwardly from the virtualreference line (240) of the square, and recess-adjacent-side-portionsadjacent to the recesses are displaced outwardly of the from the virtualreference line (240) of the square, as shown in FIG. 6.

With reference to FIG. 6, projection-adjacent-side-portions (203),(213), (223) and (233) adjacent to projections (201), (211), (221) and(231) are displaced inwardly of the square and recess adjacent sideportions (204), (214), (224) and (234) adjacent to the recesses (202),(212), (222) and (232) are displaced outwardly of the square.

In order to solve the above problems, the projections and the recessesare moved, in parallel, along the virtual reference line (240). Namely,if the projection (211) and recess (212) on the left side in FIG. 6 aredescribed as an example, they are moved downwardly (direction of arrows)by as much as the projection-adjacent-side-portion (203) on the upperside and the recess-adjacent-side-portion (224) on the lower side aredisplaced downwardly from the virtual reference line (240). All theprojections and recesses are moved in a similar manner.

As a result of such movements, the lengths of all theprojection-adjacent-side-portions and those of all therecess-adjacent-side-portions become equal, wherefore no unevenness isformed when the pieces interlock with each other.

Since a maximum width (201 a) of the enlarged portion of the projection(201) (this also holds for the other projections) is larger than aminimum width (202 a) of the constricted portion of the recess (202)(this also holds for the other recesses), detachment of the interlockedprojection and recess is prevented to realize assured interlocking.

As for the outer shape of the present invention, because there isunevenness within the sides of the pieces, the individual pieces thatare successively arrayed have a slight incline, as shown in FIG. 3( b)or 7. However, the uneven portions are absorbed without beingaccumulated due to the slight inclination of the respective pieces, asshown in FIG. 4( b). Therefore, the resulting external appearance is thesame as the external appearance produced when the pieces are normallyarrayed in horizontal and vertical directions.

Since the unevenness is at the projections and recesses and the piecesare only slightly inclined, as can be understood from FIG. 7, theappearance is that of arrayed squares and therefore not impaired.

By the above construction, the interlocking portions can besatisfactorily formed, even in small-size pieces, and sufficient imageinformation in the center of the pieces is ensured. This constructioncontributes to an improvement in the interlocking property at the timeof assembling the jigsaw puzzle and a reduction in production cost.

When creating this type of sophisticated cutting die, with a size of 2cm or smaller, accuracy could not be generated when the pieces wereadjacent to each other, as shown in FIGS. 10( c) or 11, and very preciseworking was necessary. Thus, in the embodiment of the present invention,it is proposed to arrange the pieces in an isolated manner as shown inFIG. 5. If the pieces are arrayed adjacent to each other as shown inFigure (c) or 11 and die cut, the respective pieces are compressedinwardly at four sides and slightly shrink, thereby reducing theinterlocking property when being fitted together. In the case ofarranging the pieces in an isolated manner as in the presentapplication, the size of the cutting die can be so designed as to beslightly larger than the original shape and the interlocking propertycan be maintained, even if the pieces are compressed.

Particularly, in the case of printing the respective pieces withgradations, as in this embodiment, or in different solid colors, therespective pieces can be printed completely by arranging the pieces inan isolated manner, as shown in FIG. 5.

Next, the piece surface display method relating to the present inventionwill be described.

The present invention lacks a specific image that is recognizable by theindividual pieces, even when divided, as in an ordinary jigsaw puzzle.In addition, because each piece can be arranged in upward, downward,leftward and rightward directions, there is the problem of being unableto give a player the pleasure of comparing and arranging the respectivepieces based on information of a complete image, as with ordinary jigsawpuzzles. Namely, since subtly different gradation patterns are displayedon the surfaces of the respective pieces and many pieces are similar, itis difficult to specify correct pieces and to judge the orientations ofthe pieces from the image. Hence, the game-playing property is notnecessarily high. If anything, monotonous trial and error are repeatedtoward completion, which may bore the player.

Accordingly, it is proposed to provide a marking, in addition to theimages on the piece surface of the present invention, to allow theplayer to specify the pieces and recognize orientations of the pieces.

Normally, as disclosed in patent reference 2, the marking is made byassigning numbers to the undersides. However, in such a case, it iscumbersome to confirm the orientations of the pieces when trying toassemble the pieces with the topsides facing upward. If the pieces areassembled with the undersides facing upward, this problem is solved, butbrings about other problems such as that the original pleasure of thejigsaw puzzle, to assemble a picture little by little, is lost and thepieces are disrupted when the entire puzzle is turned upside down aftercompletion. If the numbers are printed on the top surfaces, theseproblems are solved, but the aesthetic appearance is impaired when thecompleted image is viewed. If the printed numbers are inconspicuouslysmall, it would be cumbersome to distinguish the pieces upon assemblingthem.

Accordingly, in the present invention, short-distance visible marking isapplied taking advantage of a difference between two or morereflectances, glazes, or surface roughnesses in addition to the image onthe surface. The above gradation marking corresponds to the informationof a complete image, such as a landscape or a person, in ordinary jigsawpuzzles. In the present invention, by assigning short-distance visiblefigures in addition to the complete image information, the pieces areselected and the orientations thereof are judged while the assignedfigures are compared with a solution diagram as shown in FIG. 2. Thus,the player can continue assembling the pieces as if he were playing anordinary jigsaw puzzle. In addition, in a completed state, the figuresused to distinguish the pieces and the orientations thereof are madeunrecognizable at a certain distance or longer, so that the completeimage can be enjoyed.

In this embodiment, the marks are glazed by printing UV varnish to givea diffuse reflectance that is different from the one given by gradationimage printing. Thus, marks can be clearly visible at a short distance.

The player can assemble the puzzle based on the overall impression ofthe image and the short-distance visible marks. In addition, printingthe same marks on the undersides using a standard printing methodenables the pieces to be easily searched. Even in such a case, theorientations of the pieces are judged by the short-distance visiblemarks on the top surfaces.

As shown by dotted line in FIG. 1( a), the short-distance visible markis printed together with the pattern on the piece of this embodiment.FIG. 1( b) is a diagram showing only the short-distance visible mark insuch a manner that the mark is easily recognizable. A rather largefigure of, for example, a mobile phone is arranged as the short-distancevisible mark in the center of the piece. In this mobile phone figure,the vertical direction can be clearly distinguished by the antenna (20),monitor screen (21) and dialing keys (22), and the orientation of thepiece (1) can be understood based on the orientation of the mobile phonefigure.

FIGS. 8( a) and (b) show real pictures of the piece of the presentinvention. FIG. 8( a) shows a picture of the piece photographed fromtop, and FIG. 8( b) shows a picture of the piece photographed frombelow. The top surface of this piece is first printed with a gradationpattern, then entirely with matte varnish, and lastly with a mobilephone mark using UV varnish.

When light is incident on the varnished surface, reflected intensitydecreases as the angle of incidence is more perpendicular, so that whatis printed on the paper surface is visible through a layer of varnish.When viewed from the front, as in FIG. 8( a), the presence of the markis very difficult to see. In other words, the marks are difficult to seewhen the completed puzzle is viewed.

However, when light is obliquely incident, the surface with smooth UVvarnish applied thereto reflects light based on the law of reflection oflight, whereas light having been incident on the matte varnish or papersurface is perceived as scattered light. Due to this difference, themark can be seen, as in FIG. 8( b), when the piece is obliquely viewed,and can be easily used as a clue at the time of assembling the piece.

When the completed puzzle is viewed at a distance, the marks arecolorless and therefore hard to see, whereas the top surfaces of theoriginal pieces are single-color printed or color printed, causing onlythe original jigsaw puzzle image to be visible.

Since it is a general practice to apply polyvinyl alcohol resin glue tothe top surface and glue the respective pieces after the jigsaw puzzleis completed, the marks become more difficult to see due to the gluecoating. This process makes the short-distance visible marks of thepresent invention that can be seen only when the pieces are seen at ashort distance.

As shown in FIG. 2, the marks used in this embodiment are single-colormodeled designs and include signs, characters and character strings inaddition to animal figures, plant figures, tool figures, food figures,industrial product figures, and vehicle figures, etc. These designs mustmake orientation discrimination easier and make the pieces moredistinguishable from the other pieces. Further, it is desirable toprovide certain meanings so that the player can enjoy seeing them. Forexample, it is preferable that the appropriately modeled designsthemselves are enjoyed if the designs are marks, whereas thegame-playing property is enhanced using brisk words such as “GO!” and“OH!” if the designs are signs or characters. The player can also enjoythe same attempt as with ordinary jigsaw puzzles such as sorting out ofthe pieces according to similar marks beforehand so that the correctpieces can be more easily found.

The present invention is characterized in that arbitrary images can bemade up by arraying the pieces in different manners using the marks,while keeping the pleasure of assembling the pieces based on a pictureas with ordinary jigsaw puzzles by independently assigning the mark toeach piece as described above.

The array table as shown in FIG. 2 can be generated through imageprocessing by a computer or by manually preparing a solution imagebeforehand by trial and error and recoding the array of the solutionimage. Note that surface images of the pieces of the present inventionare not limited to those of this embodiment and one complete solutionimage may be set, as traditionally.

Although the UV varnish is used in this embodiment, ordinary varnish orany production method may be used provided that the reflectance, glaze,and surface roughness of the short-distance visible mark parts thatdiffer from other parts. For example, the glaze of the mark parts may bereduced by printing a mixture of paint and fine particles. Further, theshort-distance visible mark parts or the other parts may be polished tochange surface roughness.

Utilizing such characteristics, the present invention proposes a displaymethod allowing for piece recognition and orientation recognition, whichis not found in conventional jigsaw puzzles.

FIG. 9 is a plain view of a tray (2) used to array the pieces of theabove jigsaw puzzle. This tray (2) is composed of a flat plate body, andguide lines (21) indicating the outer shapes of the pieces of the puzzleare printed in horizontal and vertical directions on the top surfacethereof. Further, column indicators (22) indicating columns A to O androw indicators (23) indicating rows 1 to 20 in correspondence with theguide lines (21) are provided along the entire peripheral edge. Theplayer can array the pieces, for example, according to a matrixrepresentation displayed on the array table of the solution.

Since the pieces of the present invention have no characteristic outershape, it is not possible to partially assemble the pieces from thosethat can be fitted together unlike ordinary jigsaw puzzles. However, byusing this tray (2), the pieces can be directly arranged at correctpositions based on the array table even if being randomly picked up,wherefore the game can be enjoyed in the same manner as conventionaljigsaw puzzles are enjoyed.

A peripheral portion (24) along which the pieces are arrayed may beshaped to be folded to prevent detachment of the pieces if being made ofpaper as in this embodiment, whereby the pieces can be so fixed as notto move while being assembled. This tray may be a resin or wooden traywhose periphery was worked into a frame beforehand.

Piece shapes are painted out in the entire column H (25) and the entirerow 11 (26), so that row and column positions are displayed to be easilydistinguishable even in intermediate parts.

This tray (2) can also be used as a base plate for the pieces at thetime of decoration by applying glue onto the top surface of theassembled puzzle to glue the pieces and cutting off the row and columnindicators (22), (23) after drying. Cutoff lines may be formed along therow and column indicators (22), (23) beforehand, so that the indicatorscan be easily cut off.

REFERENCE SIGNS LIST

-   1 piece according to the present invention-   10 projection-   11 recess-   12 center point-   20 short-distance visible mark (antenna part)-   21 short-distance visible mark (monitor screen part)-   22 short-distance visible mark (dialing keys part)

1. A jigsaw puzzle piece capable of interlocking with other pieces byinterlocking portions each composed of at least one pair of projectionsand recesses and provided on a corresponding one of four sides of asquare, wherein: the respective sides are formed to be point symmetricalwith respect to a center of the square; and the pieces can interlockwith other pieces in four upward, downward, leftward and rightwarddirections, whereas the respective sides of the piece are shaped suchthat projection-adjacent-side-portions adjacent to the projections aredisplaced inwardly of the square and recess-adjacent-side-portionsadjacent to the recesses are displaced outwardly of the square withrespect to a virtual reference line composed of sides of a square, theprojections and the recesses are moved on the virtual reference line bydistances corresponding to respective displacements, thereby preventingunevenness on sides of adjacent pieces when the pieces interlock withother pieces, and a maximum width of enlarged portions of theprojections is set larger than a minimum width of constricted portionsof the recesses to prevent detachment of interlocked projections andrecesses.
 2. A jigsaw puzzle piece capable of interlocking with otherpieces by including interlocking portions each composed of a projectionand a recess and provided on a corresponding one of four sides of asquare, wherein: display is made due to a difference between two or morereflectances, glazes or surface roughnesses.
 3. A tray used to array aplurality of pieces according to claim 1, wherein: an outer edgecoincides with the size of a jigsaw puzzle in a completed state; a framebody is prepared along four sides to prevent detachment of the pieces;and row and column indicators are provided to indicate vertical andhorizontal positions of the respective pieces.
 4. A tray used to array aplurality of pieces according to claim 2, wherein: an outer edgecoincides with the size of a jigsaw puzzle in a completed state; a framebody is prepared along four sides to prevent detachment of the pieces;and row and column indicators are provided to indicate vertical andhorizontal positions of the respective pieces.